Battery empty because of alarm system ???

Hello guys, I bought a runner with alarm system remote start and so. At the beginning where I bought the scooter he went on with e-starter and also with fenrbetriebe, after a day the battery is empty. ( Maybe the previous owner drove the scooter a bit before the purchase so that the battery is charged. Well now he only goes with kick starter. No matter that is not the thing. Can it be that the battery goes through the alarm system empty? Still something, if I the scooter so bit b ewege goes the alarm net, no sound ? What is it about. Thanks for the answers MfG